[Linux-kernel-mentees] [PATCH v2 12/15] scsi: 3w-9xxx: use generic power management

[Vaibhav Gupta]

Drivers using legacy PM have to manage PCI states and device's PM states
themselves. They also need to take care of configuration registers.

With improved and powerful support of generic PM, PCI Core takes care of
above mentioned, device-independent, jobs.

This driver makes use of PCI helper functions like
pci_save/restore_state(), pci_enable/disable_device(),
pci_set_power_state() and pci_set_master() to do required operations. In
generic mode, they are no longer needed.

Change function parameter in both .suspend() and .resume() to
"struct device*" type. Use to_pci_dev() and dev_get_drvdata() to get
"struct pci_dev*" variable and drv data.

Compile-tested only.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40 at gmail.com>
---
 drivers/scsi/3w-9xxx.c | 30 ++++++++----------------------
 1 file changed, 8 insertions(+), 22 deletions(-)

diff --git a/drivers/scsi/3w-9xxx.c b/drivers/scsi/3w-9xxx.c
index 3337b1e80412..c15dcfda3957 100644
--- a/drivers/scsi/3w-9xxx.c
+++ b/drivers/scsi/3w-9xxx.c
@@ -2191,10 +2191,10 @@ static void twa_remove(struct pci_dev *pdev)
 	twa_device_extension_count--;
 } /* End twa_remove() */
 
-#ifdef CONFIG_PM
 /* This function is called on PCI suspend */
-static int twa_suspend(struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused twa_suspend(struct device *dev)
 {
+	struct pci_dev *pdev = to_pci_dev(dev);
 	struct Scsi_Host *host = pci_get_drvdata(pdev);
 	TW_Device_Extension *tw_dev = (TW_Device_Extension *)host->hostdata;
 
@@ -2214,32 +2214,21 @@ static int twa_suspend(struct pci_dev *pdev, pm_message_t state)
 	}
 	TW_CLEAR_ALL_INTERRUPTS(tw_dev);
 
-	pci_save_state(pdev);
-	pci_disable_device(pdev);
-	pci_set_power_state(pdev, pci_choose_state(pdev, state));
-
 	return 0;
 } /* End twa_suspend() */
 
 /* This function is called on PCI resume */
-static int twa_resume(struct pci_dev *pdev)
+static int __maybe_unused twa_resume(struct device *dev)
 {
 	int retval = 0;
+	struct pci_dev *pdev = to_pci_dev(dev);
 	struct Scsi_Host *host = pci_get_drvdata(pdev);
 	TW_Device_Extension *tw_dev = (TW_Device_Extension *)host->hostdata;
 
 	printk(KERN_WARNING "3w-9xxx: Resuming host %d.\n", tw_dev->host->host_no);
-	pci_set_power_state(pdev, PCI_D0);
-	pci_enable_wake(pdev, PCI_D0, 0);
-	pci_restore_state(pdev);
 
-	retval = pci_enable_device(pdev);
-	if (retval) {
-		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x39, "Enable device failed during resume");
-		return retval;
-	}
+	device_wakeup_disable(dev);
 
-	pci_set_master(pdev);
 	pci_try_set_mwi(pdev);
 
 	retval = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
@@ -2277,11 +2266,9 @@ static int twa_resume(struct pci_dev *pdev)
 
 out_disable_device:
 	scsi_remove_host(host);
-	pci_disable_device(pdev);
 
 	return retval;
 } /* End twa_resume() */
-#endif
 
 /* PCI Devices supported by this driver */
 static struct pci_device_id twa_pci_tbl[] = {
@@ -2297,16 +2284,15 @@ static struct pci_device_id twa_pci_tbl[] = {
 };
 MODULE_DEVICE_TABLE(pci, twa_pci_tbl);
 
+static SIMPLE_DEV_PM_OPS(twa_pm_ops, twa_suspend, twa_resume);
+
 /* pci_driver initializer */
 static struct pci_driver twa_driver = {
 	.name		= "3w-9xxx",
 	.id_table	= twa_pci_tbl,
 	.probe		= twa_probe,
 	.remove		= twa_remove,
-#ifdef CONFIG_PM
-	.suspend	= twa_suspend,
-	.resume		= twa_resume,
-#endif
+	.driver.pm	= &twa_pm_ops,
 	.shutdown	= twa_shutdown
 };
 
-- 
2.27.0